A turbine engine includes one or more shafts, together forming a rotor, which are mounted for rotation in several bearings, which can include rolling bearings. Any unbalance on the rotors results in dynamic loads. Reducing dynamic loads can be achieved by introducing a flexible support for one or more of the bearings, instead of mounting the bearings directly in a stationary frame. The flexible support can be integrated with a part of the bearing. The flexible support can have a stiffness reduced to a level which allows to lower dynamic loads to levels acceptable for the engine and airframe. To allow certain displacements of the bearing together with the rotor, a clearance between the flexible support and a frame is provided.
In conditions of high unbalance the dynamic loads are in most cases high enough to close the gap between the flexible support and a frame. In such cases the dynamic characteristic of the engine changes due to formulation of a new, stiffer load path from a bearing directly to a frame.
Accordingly, there is a need for a bearing support system which would give required flexibility during high unbalance conditions, without affecting engine dynamics in normal operating conditions.